Rock-drilling machine



Maya, 1928.

J. J. GRANT ROCK DRILLING MACHINE Filed May 27. 1926 INVENTOR JoH/v JAMEs GRANT BY l ATTORNEYS Patented May 8, 1928.

'UNITED STATES PATENT OFFICE.

JOHN JAMES GRANT, OF VANCOUVER, BRITISH COLUMBIA, CANADA.

ROCK-DRILLING MACHINE.

Application filed May 27,

My invention relates to improvements in drilling machines for subaqueous or other Work and particularly where'deep holes are chine and its drill rods without danger'of such fluid gaining access to the working cylinder, and when steam is used, iorreciproeating the piston, and water used for projection through the drill, for preventing condensation from forming around the working '15 areas of piston or cylinder. Further objects are to provide a drill head construction which is inherently strong and which will serve to prevent the leakage of fluid under pressure from between the drill chuck and 29 the drill head.

The invention consists essentially of a drilling machine of the rotating, reciprocating piston type having a sleeve extending from one end of the piston to the other and through which water or other fluid, may be forced at any desired pressure, and from thence passed throught-he drill rods and drill, which fluid is used for the purpose of cleaning the drill and ejecting the cuttings from the hole, as will. be more fully described in the following specification, in

The drawing is a longitudinal section of the invention.

The numeral 1 indicates generally a cylinder block having a liner 2, and an upper cylinder head 3, and a lower cylinder head 4:,

the cylinder block 1 is providedwith ports 5 through which operating pressure such as steam or water is directed from a suitable valve mechanism 6, to impart a reciprocatory motion to a piston 7. The piston 7 is provided with a rifle bar 8 and has a ratchet rotating mechanism 9 which is housed between the upper head 3 and cover sleeve 10. The numeral 11 indicates a cap fitted upon the outer end of the cover sleeve having an inlet 12 to which a pressure hose 13 is adapted to be connected. The parts thusfarenumerated are in essential, details similar to those in .use in rock or submarine drilling machines generally, except that the rifle bar 8 is reversed to extend into the cover sleeve 10in which it is slidably supported.

The piston and the rifle bar 8 are bored axially at 14; throughouttheir length, the

1926. Serial No. 1124570.

bore also extending throughout the length.

of the piston rod 15. The central portion of the bore is enlarged for a length somewhat greater in extent than the-length of the piston, as at 16, the purpose of which will here inaiter appear. The piston r0d15 is provided with an enlargement 17 which is recessed axially as at 18V to form a chuck for the reception of a drill head 19, which drill head is adapted to be secured to the chuck by bolts 20. At the upper. extremity of the recess 18 a further recess 21 isprovided for thepurpose of receiving a packing washer 22 and the flanged end 23 of a. sleeve or blower tube 24, which sleeve extends throughout the length of the bore 14- and is connected to the upper end; of the-rifle bar 8 by a suitably packed flanged collar 25, thus providing a continuous passage extending throughout the length of the piston rod and rifle bar and through which fluid maybe forced from the hose 13 to thedrill head 19 at any pressure. The upper extremity of the rifle bar 8 is turned down to cylindrical form as at 26, such cylindrical portion being slidahly movablethrough a suitable packing gland 27 carried in the upper end of the cover sleeve 10, which gland. servesto prevent fluid admittedto the cap 11 through the hose 13 from flowing along the sides or corrugations of the rifle bar and into the working cylinder. In the enlargement l6 of'the bore 14 andsurrounding the sleeve 2&1 may prefer to fix a tubular insulation 28 of asbestos or other material, so that when water, is used for flushing the drill rod and drill, and when steam; is used for actuating the piston '7, the chilling effect of the water in passing through the sleeve 24 will be prevented from condensing the steam within the working parts of the piston and cylinder and impairing the efficiency of the machine.

It will be noticed that since the sleeve 24 is secured at opposite ends to thepiston rod ,15 and the rifle bar 8, it will move thereto by the bolts 20 previously described.- Ex

Having thus described the several parts of my invention Iwill now briefly explain its function.

A suitable drill (not shown) having an axial passage, is fitted to the drill rod connection 32 and is entered into the hole to be drilled. The steam air or other fluid oresa 1 sure 18 admitted to the cylinder through the valve mechanism 6 to impart reciprocation and rotation to the piston, the drill rods, and the drill. hen air is intended to be used for actuating the piston and the temperature differential between the cylinder and the axial bore of the piston is not conducive to the formation of condensate within the Working spaces, the sleeve 24- and the tubular insulation 28 may be omitted, since the seal between the axial bore and the working spaces of the cylinder is applied upon the cylindrical portion 26 of the rifle bar 8. \Vater or other fluid is caused to flow through the inlet 12 of the cap 11 passing downwards through the sleeve or blower tube 24, the drill head 19, the drill rods, and ultimately the drill itself. Since the water or other fluid entering the cap 11 is prevented from reaching the workingparts of the machine by the packing glands 2'? it will be obvious thatsuch water may be admitted at sufiiciently high pressure as to positively prevent any-choking of the actual passage of the drill! In the structure shown the only point of possible communication between the working cylinder and sleeve 2 L would be along the inner side walls of the cover sleeve 10, but as this is definitely closed off by the gland 27 it will. be obvious that any pressure can be forced through the sleeve without danger of leakage to the working parts of the machine. By providing the drill head 19 with a flange 29 adapted for engagement with the face of the chuck 17, the impact of the piston is received over a large area, materially reducing damage or breakage to drill rods over that obtained in other methods of construction.

What I claim as my invention is:

1. In a rock drilling machine having a piston endwise movable in a cylinder having opposing heads, said piston having a piston rod extending through one cylinder head to which a drill rod is adapted to be connected, a rifle barconnected to the oppo site end of the piston through the other cylinder head, said rifle bar having a cylindrical outer extension, said piston rod and rifle bar having an axial passage through which fluid is adapted to flow to the drill rod, and a packing gland surrounding the cylindrical portion of the rifle bar forming a sealed joint between the axial passage and the working spacesof the cylinder.

2. In a rock drilling machine the combination of a cylinder, a piston operating therein andequipped with a piston rod extendingthrough one of the cylinder heads, a rifle bar connected to the piston and extending through the remaining cylinder head, a tube mounted in aligned passages formed in the piston, piston rod and rifle bar, an abutment carried by one end of the tube and engaging the outer end of the rifle bar, a flange at the other end of the tube, disposed opposite a shoulder formed by euga'gement of the pistonrod passage, and insulating materialf interposed between said tube and the surrounding wall portions of the piston and the piston rod.

Dated at Vancouver, B. (1., this 12th day of May, 1926.

JOHN JAMES GRANT. 

